B92SiQL钢的高温流变行为及变形机制研究  

Study on High-temperature Flow Behavior and Deformation Mechanism of B92SiQL Steel

作　　者：王庆娟[1] 党雪 杜忠泽[1] 王钦仁 何泽恩 齐泽江 WANG Qingjuan;DANG Xue;DU Zhongze;WANG Qinren;HE Zeen;QI Zejiang(School of Metallurgical Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)

机构地区：[1]西安建筑科技大学冶金工程学院,西安710055

出　　处：《材料导报》2023年第21期247-254,共8页Materials Reports

基　　金：国家自然科学基金(52174371);陕西省科技厅企业联合基金(2021JLM-33)。

摘　　要：B92SiQL钢因高强度及抗扭转能力在预应力镀锌钢丝领域备受青睐,但热加工参数对其变形行为及性能产生重要影响。本研究对B92SiQL钢进行了变形温度为1173~1373 K、应变速率为0.1~20 s^(-1)的热压缩实验,并基于Zener-Hollomon参数和线性拟合,建立了应变补偿型Arrhenius本构模型。结果表明,流变应力随变形温度的升高或应变速率的降低呈减小趋势,B92SiQL钢的热变形激活能(Q)约为305.865 kJ/mol。该模型得到流变应力预测值与实验值的线性相关系数(R)约为0.994,平均绝对相对误差(AARE)约为2.800%。在较低变形温度下,微观组织中依然存在被拉长的原始晶粒;在1373 K-0.1 s^(-1)热变形条件下,B92SiQL钢几乎发生了完全的动态再结晶(DRX),晶粒产生明显粗化;应变速率增大至10 s^(-1)时,晶粒尺寸明显减小。根据加工硬化率与流变应力曲线确定了B92SiQL钢发生DRX的临界应力和应变,得到临界条件与Z参数呈指数关系。根据传统的Avrami方程建立了B92SiQL钢的DRX动力学模型,对预测结果与实验数据进行了比较,结果表明该模型具有较高的预测精度。B92SiQL steel is favored by prestressed galvanized steel wire for its high strength and torsional resistance,and the thermal processing para-meters have an important impact on its deformation behavior and properties.In this study,the thermal compression experiments of B92SiQL steel were conducted over the range of deformation temperatures from 1173 to 1373 K and strain rates from 0.1 to 20 s^(-1).The strain-compensated Arrhenius constitutive model was established based on the Zener-Hollomon parameter and linear fitting.The results showed that the flow stress decreased with increasing deformation temperature or decreasing strain rate.The thermal deformation activation energy(Q)of B92SiQL steel is about 305.865 kJ/mol.The linear correlation coefficient(R)between the predicted values and experimental values of flow stress obtained from this model is about 0.994,and the average absolute relative error(AARE)is about 2.800%.At lower deformation temperatures,the elongated primary grains were still present in the microstructure.At the thermal deformation condition of 1373 K—0.1 s^(-1),nearly complete dynamic recrystallization(DRX)occurred and the grains produced significant coarsening.The grain size was significantly refined when the strain rate increased to 10 s^(-1).The critical stress and strain for the occurrence of DRX were determined from the curve of work-hardening rate and flow stress,and the critical condition was obtained to be exponentially related to the Z parameter.The DRX kinetic model of B92SiQL steel was deve-loped based on the conventional Avrami equation,and the predicted results were compared with the experimental data,which indicated that the model had high prediction accuracy.

关 键 词：B92SiQL钢 流变行为 本构模型 变形机制 动力学模型 

分 类 号：TG142[一般工业技术—材料科学与工程]